STERLING, Colo. (AP) — Authorities say a teenage couple accused of killing the boy’s grandparents told them they planned the murders so he could get his inheritance.

Nineteen-year-old Brendan Lee Johnson and 18-year-old Cassandra Ann Reib appeared in court Wednesday in Sterling, a small city on Colorado’s rural northeastern plains, a day after they were arrested in the deaths of Charles and Shirley Severance, both 70.

Arrest affidavits show both teens told police they planned to kill Johnson’s grandparents by smothering them with pillows as they slept. Police say Reib told them Johnson wanted to inherit their house and $20,000 from their checking account.

Police say the teens dumped some of Shirley Severance’s remains near Sterling and others about 30 miles away in Lorenzo, Nebraska. Police discovered Charles Severance’s body in his home last week.